properties Nadine KARAKI International Conference and Exhibition on Biopolymers and Bioplastics August 10122015 San Francisco USA Supervisors Lionel Muniglia Abdulhadi ID: 362357
Download Presentation The PPT/PDF document "Novel phenolic derivatives of pectin: en..." is the property of its rightful owner. Permission is granted to download and print the materials on this web site for personal, non-commercial use only, and to display it on your personal computer provided you do not modify the materials and that you retain all copyright notices contained in the materials. By downloading content from our website, you accept the terms of this agreement.
Slide1
Novel phenolic derivatives of pectin: enzymatic synthesis and properties
Nadine KARAKI
International
Conference
and Exhibition on
Biopolymers
and Bioplastics
August 10-12,2015 San Francisco, USA
Supervisors: Lionel Muniglia, Abdulhadi Aljawish, Catherine Humeau, Jordane JasniewskiSlide2
Objective of studyMaterials and methods Results and discussionConclusion
PLanSlide3
Importance of the studyOXYDATION
Novel architecture
(supra) molecular –antioxidant
ANTIOXIDANTS
Direct and indirect enzymatic grafting
Ingredient with double functionality and novel colorSlide4
System definitionBiopolymer:
Citrus pectinPhenolic compound: Ferulic acid
Enzyme: Laccase from Myceliophtora
thermophilaSlide5
Studied
biopolymer: pectin
Poly-Galacturonic
acid
(polyanionic)
Texturant
Gelling
AgentStabilizing
agent
Cosmetics
Pharmaceutics
F
ood
Forte
exprtise
sur le chitosane, thèse d’Abdul, un des rares poly cationiques
Pectine: gélifiante en fonction de la force ionique
-naturellement
féruloylées
Notre but est donc: assembler des composés naturelles
-
integrer
des composés phénoliques qui se trouvent dans la nature pour
aug
l’activité
antioxy
-
remimer
la nature car on essaie de faire pec
ferulo
Citrus
Pectin
Rajpurohit
et al., 2010
Limitation
F
eruloylated
pecti
n
is taxonomically
widespread
but of low
abundance
HG-I , RG-I and RG-II
Biosynthesis of Pectin; Harholt et al, 2010
(Hairy region)
(
Smooth
region
), Slide6
phenolic compound: Ferulic acid
Secondary metabolite in plants, red fruits
Hydroxycinnamic acid
derivative
Natural antioxidant reactive against the Radical Oxygen Species (ROS)
Structure:
Diabetes
Aging
Cancer
C.V.D
.
Cardiovascular
disease
Asthma
Hypertension
3-
(4-hydroxy-3-methoxy-phenyl)prop-2-enoic
acid
Kumar et al., 2014Slide7
Polyphenol oxidase: laccase (EC.1.10.3.2)
Copper-containing oxidase enzymes Found in many plants, fungi, and microorganisms.
Oxidize phenolic
compounds oligomers and thus
coupling phenoxy radicals (Sun et al., 2013) or reacting with nucleophilic
functions in polymers
and thus allowing the grafting.
Delignification of lignocellulosics, crosslinking of polysaccharides, bioremediation of the toxic chemicals
(
Aljawish
et al.,2015)Slide8
ObjectivesVerification of the feasibility of an enzymatic modification of pectin
Evaluation of the impact of enzymatic modification on the structure and the properties of the pectin :
Optical proprietyAntioxidant activity
Physico-chemical proprietiesSlide9
Planned strategy
Direct functionalization
Indirect
functionalization
Ferulic
acid+ enzyme
POXPOX+ pectin Pectin
-POX
Ferulic acid + pectin + enzyme pectin-F
Enzymatic
functionalization
Solutions are
freeze-dried
Powder
washed
with
organic
solvent
Storage in
dessicatorSlide10
Pectin-FPectin
-POX
UV-Vis
Physico-
chemical
properties
Phenolic
content
Hygroscopy
R
adical
scavenging
activity
Structural
characterization
Native
pectin
(
P
ectin
-N)
CHARACTERIZATION OF PECTIN DERIVATIVES
SEM
DPPH
ABTS
Color
intensity
LC-MS
FTIR
NMRSlide11
Results and discussionSlide12
LC-MS analysis of galacturonic acid (GA): main unit of pectin
FA-Laccase
FA-GA
GA
-Laccase
FA-GA-Laccase
FA-galactose-Laccase
A novel peak corresponding
to the product formed having
m/z=629
The carboxyl group is implicated in the enzymatic modification
P.S: FA=Ferulic
acid
Positive mode
www.wikepedia.comSlide13
Surface analysis (sem)
Pectin
-POX
Pectin
-F
Pectin
-N
P
ectin-POX (scaly surface) physical
adsorption of
POX
onto
pectin
Pectin-F (smooth surface) the aromatics were intercalated inside the structure
The
morphology
changes
were attributed to effects of the functionalization
reactionSlide14
Phenolic content and samples color
Samples
Concentration of gallic acid Equivalent mg /g of dry weight
Native pectin
9.9 +/- 0.8
Pectin-F
54.7 +/- 0.3
Pectin-POX
32.6 +/- 1.2
Direct
enzymatic
oxidation
leading
to
pectin
-F
showed
the
highest
phenolic
content
Samples
L*
(
Light)
a*
(
Red)
b*
(
Yellow)
C* Pectin-N78.8 +/- 0.6
3.2
+/- 0.1
12.7 +/- 0.613.1 +/- 0.65
Pectin
-F
57.7 +/- 0.3
10.7 +/- 0.1
26.4 +/- 0.128.47 +/- 0.65Pectin-POX
70.0 +/- 1.9
6.4 +/- 0.6
24.4 +/- 0,4
25.23 +/- 0.69
The
color
is
due to the
oxidation
reaction
Pectin
-F has the
most
intense
color
the
highest
content of
phenols
Color parameters (
Datacolor
)
Phenolic content (
Folin
&
Ciocalteu
)
(
Color intensity)
(C) = (a*
2
+ b*
2
)
1/2Slide15
Hygroscopy (Dynamic vapor sorption)
RH < 45 %
pectin-F
is the less hygroscopic
RH > 45 % pectin-N is the less hygroscopic
The storage of pectin-F and pectin-POX is more stable inside an environment of less than 50 % of humidity
The addition of phenolic group to pectin makes it more hydrophobicSlide16
Antiradical activity
EC50 (mg/ml)
Pectin-N
Pectin-F
Pectin-POX
Scavenging ability on ABTS
+•116.2 +/- 3.9
11.2 +/- 0.8
11.5 +/-
1.2
Scavenging ability on
DPPH•
29.5 +/- 0.3
1.4 +/- 0.2
9.0 +/- 0.1
Modified
pectin
has
better
antiradical
activity
due
to
it
highest
content of
phenol
When
EC50
the
a
ntioxidant
activity
Slide17
ConclusionTwo enzymatic approaches were described to modify the biopolymer pectin
: the direct and the indirect one.Structural and physico-chemical properties were investigated : structure, surface, hygroscopy and antioxidant
Enzymatic oxidation of FA and its grafting on pectin:
Increased the pectin phenolic content, its antiradical activity and its hydrophobic nature
Led to colored pectin derivativesDecreased the roughness of surfaceSlide18
Nancy, France
LebanonSlide19
Jeita-lebanon
Thank
you
for your attention